KR20110077288A - System for providing programable logic controller software development environment - Google Patents

Abstract

PURPOSE: A PLC software development environment providing system is provided to modularize a PLC software in an object-oriented point of view, segment a module in a top-down mode, remove inter-module dependence to develop software with improved legibility and reusability and make the software resources. CONSTITUTION: A module generating unit generates a module used for a PLC(Programmable Logic Controller) software. An architecture configuration unit layers modules comprising the PLC software. A data model generating unit processes data used in each module and generates a data model having a structure in which the access of other modules except for a corresponding module is restricted. A storage unit(200) stores the module and the data model generated by a PLC software machine(100).

Description

PLC software development environment providing system {SYSTEM FOR PROVIDING PROGRAMABLE LOGIC CONTROLLER SOFTWARE DEVELOPMENT ENVIRONMENT}

The present invention relates to a system for providing a programmable logic controller (PLC) software development environment, and more particularly, to a system for providing a PLC software development environment for supporting the development of PLC software having excellent readability, reusability, and maintainability. It is about.

In general, a programmable logic controller (PLC) is a basic function that utilizes functions such as relays, timers, and counters through digital or analog I / O modules. It is a digital electronic device that directly controls various kinds of mechanical equipment by using PLM (Programmable Logic Memory) to enable feedback control with additional functions such as data operation, arithmetic operation and data transmission. It is a core device that is essential to product production and factory automation.

PLC programming languages include LD (Ladder Diagram), Function Block Diagram (FBD), Instruction List (IL), Structure Text (ST), Sequential Function Charts (SFC), and the like.

In general program structure and control logic processing method, the input CPU reads the status of input through the process of reading input data, and executes the operation sequentially from the beginning to the end of the program using the recognized information as the condition or data and writes the output data. Run

In general, the PLC of the steel process, as shown in Figure 1, when the data is input through the input module, the system status check module diagnoses the state of the system to handle the error if the abnormal state and in the facility control module if the normal state Process logic for facility control. The facility control module performs facility status checks, various control modes, and calculations for each facility to be controlled, and processes logic for controlling the target driver. After the control module for all the facilities is performed, a signal is output through data writing.

However, various types of PLCs are introduced in the steel process, and since PLC software is affected by hardware and development environment, there are many differences in PLC software between similar processes. Will be different. As a result, it requires a lot of manpower and time to improve facilities and change PLC software when developing new steel grades, and also reduce the maintainability of PLC software. In addition, the modification of the control code is a reality that it is very difficult to reuse and modify the existing information unless a directly related worker is accompanied. In addition, even if the same function is performed according to a small change in the external environment, PLC software modules are not compatible with each other, unnecessary redundancy is developed, cost and time are consumed, and PLC software modules have no common structure. Difficult, low readability of PLC software code.

Conventional PCL software uses the global memory commonly used in PLC software as a method for managing the data required for control and for transferring data between modules.

Fig. 2 is a block diagram showing the general data management structure of PLC software. Because of the convenient accessibility to global memory, developers can write optimized programs, but without appropriate restrictions and rules, there is a high coupling between modules. Occurs. High coupling reduces the maintenance and maintainability of the program, and acts as a deterrent to readability and reusability.

Modules constituting the program to improve the readability of the program based on the data management structure using the global memory, as shown in FIG. 3, have a corresponding physical or logical storage to store variables used in each module. Have. For example, in Figure 3 module 1 allocates a local repository of memory block 1 to store variables to be used in its implementation. By maintaining the correspondence as shown in FIG. 3, the developer can track the meaning of the memory address using the name of the memory block used in the program. The symbol names given to each memory address along with the memory address address provide developers with higher readability.

However, since a module can still access data existing in a storage other than its own storage without any limitation, it cannot fundamentally solve the problems of readability, reusability, and maintainability.

According to the present invention, PLC software, which is developed differently according to differences in PLC development environment, preference of PLC software developer, external environment, etc., can be modularized in an object-oriented perspective, and the modules are subdivided in a top-down manner, and the dependencies between modules are used. It can reduce the software development time and maintenance time by providing the environment to develop and resource the software with improved readability and reusability, and to perform new software development and software maintenance work based on it. The purpose of the present invention is to provide a PRC software development environment providing system that can improve the maintainability of the software.

The PLC software development environment providing system according to an aspect of the present invention includes a module generation unit for generating a module used for PLC software, an architecture configuration unit for layering modules constituting PLC software, and processing data used in each module. And a PLC software writer including a data model generator for generating a data model of a structure in which access of other modules other than the corresponding module is restricted, and a storage for storing the module and the data model generated by the PLC software writer. It is done.

The module generation unit may provide an environment for inputting a program and a task assigned to the module and a detailed design of each module, and generate a module based on the input contents corresponding to the provision.

The architecture generating unit provides a PLC software framework including an HMI layer, a facility manager layer, a library layer, a network manager layer, and a system function layer, and layeres modules constituting PLC software based on the PLC software framework. It is characterized by.

The HMI layer may include a module that manages an interface between a program logic controller (PLC) and a facility to be controlled.

The facility manager hierarchy is characterized in that it comprises a module in charge of the movement control of the facility to be controlled.

The library layer may include a module in charge of controlling an operation sequence and data processing of a facility to be controlled.

The network manager layer may include a module that is in charge of communication between a program logic controller (PLC) and a facility to be controlled.

The data model generation unit divides data used in each module into input / output data, reference data which is data of a corresponding module used in another module, and interface data which is data of another module used in the corresponding module. Copy the data to the module and configure the data model together with the reference data existing in the module.

The storage may store the data model by mapping the data model to a corresponding module that is allowed to access the data model.

The PLC software development environment providing system includes a module asset manager configured to store modules generated by the PLC software writer in the repository and to load modules stored in the repository to the PLC software writer, and the PLC software writer. A data model asset manager for storing a data model generated through the storage and retrieving the data model stored in the storage to the PLC software creator, and an operating condition asset manager for storing operating conditions of the equipment to be controlled And, when the user sets an operating condition or selects an operating condition stored in the asset manager for late combined conditional expressions written by the user, the selected operating condition is combined with a module generated by the PLC software writer to form a complete module. And further comprising a coupler operating conditions - St. module.

According to the present invention, the PLC software can be modularized from an object-oriented perspective, the modules can be broken down in a top-down manner, and the relationships between the modules can be structured, thereby improving the readability and maintainability of the PLC software.

According to the present invention, since the dependency between modules is removed through the inter-module interface method, the compatibility and reusability of the software module is increased, so that it is easy to modify the PLC software, which has been difficult to modify in the past, and the asset development of the PLC software becomes possible. Reduced time and software maintenance work.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention.

4 is a block diagram showing a system for providing a PLC software development environment according to the present invention.

The system according to the invention comprises a PLC software writer 100 and a repository 200.

In addition, it includes a module asset manager 300, data model asset manager 400, operating condition asset manager 500 and module-operation condition combiner 600.

Among the components of the system shown in FIG. 4, the PLC software builder 100, the module asset manager 300, the data model asset manager 400, the operating condition asset manager 500, and the module-operating condition combiner 600 are described. It may be implemented in software that can be executed in one computer or a plurality of computers connected through a network.

Each module constituting the PLC software development environment providing system according to the present invention will be described in detail as follows.

In this embodiment, the repository 200 stores modules and data models used in the PLC software.

Although not shown in detail, the storage 200 divides the modules into four layers of an HMI layer, a facility manager layer, a library and network manager layer, and a system function layer.

The HMI layer stores the modules that are in charge of the interface between the PLC and the equipment to be controlled, and the module that controls operations is stored in the facility manager layer. The module responsible for sequence control and data processing is stored in the library layer, and the module responsible for communication is stored in the network manager layer. In addition, the module corresponding to the system function is stored in the system function hierarchy.

The data models are stored in storage 200 while maintaining a one-to-one mapping relationship with the modules. The data model mapped to a specific module is composed of PLC I / O data which is input / output data, interface data which is data of another module used in the corresponding module, and reference data that collects data used by other modules as the result of the module execution. This structure of the data model restricts access to modules other than those modules. In other words, the data model allows data to be hidden inside the module.

Modules and data models stored in the repository 200 are generated and assetd by the PLC software writer 100 during previous PLC software development, and are subsequently reused in the process of developing the PLC software.

The PLC software builder 100 provides an environment for generating modules and data models and for writing new PLC software using the modules and data models stored in the repository 200.

In the present embodiment, the PLC software builder 100 includes an architecture constructing unit, a module generating unit, and a data model generating unit.

The architecture component provides PLC software framework composed of HMI layer, facility manager layer, library layer, network manager layer and system function layer, and layer the modules that make up PLC software based on PLC software framework.

The architecture component loads a module stored in the storage 200 and uses the module as it is, or uses a module generated through the module generator as necessary.

5 is a diagram showing the architecture of the PLC software according to the present invention. The PLC software according to the present invention is composed of four layers: a system function layer, a library and network manager layer, a facility manager layer, and an HMI layer.

The system function hierarchy consists of the basic system functions provided by the PLC vendor. Modules in this layer are dependent on the PLC vendor, so they change every time the target PLC that makes up the plant system changes. By completely independence of these system functions into a separate layer, the modules of the upper layer are not affected by PLC type.

The library layer and network manager layer reside in the same layer and are implemented using system functions provided by the vendor.

Modules in the library layer enable the modules in the network manager layer to be used so that modules in the library layer can use a variety of communication methods when signaling to hardware. This is because the modules in charge of the devices in the library layer use various communication methods when transmitting signals to actual hardware.

In the library hierarchy, there are an actuator control module, an output device control module, and a numerical calculation algorithm module to be controlled. The network manager layer contains modules related to communication. Modules in the network manager layer are implemented to support all protocols used in the factory.

The library layer and network manager layer play an important role in the reuse of PLC application software by enabling the upper-level modules responsible for controlling the facility to be vendor independent. Modules that act as libraries or network administrators should be managed according to their development environment. For example, even though a component that is responsible for network communication is implemented in the Siemens S7 environment, the LSIS GLOFA development environment must be newly implemented using system functions provided by GOLFA.

Most of the modules developed for the conventional software reuse belong to this layer. However, the module that acts as a driver to control the movement of the facility directly develops in various styles according to the developer. Therefore, in order to develop more efficient software reuse modules, the differences and commonalities that can be derived through analysis of all factories can be identified. It is necessary to proceed with the modularization.

The modules belonging to the facility manager hierarchy are in charge of the control of the facilities constituting the actual plant and use the modules configured in the library hierarchy for facility control, data processing, and external system interface. The part responsible for sequential control and data processing is included in the module of this layer, and it is the part that changes most according to the requirements of the system. In order to minimize the influence of changes in the surrounding environment, information hiding must be applied together with modularization.

Since the module in the library hierarchy is responsible for delivering control results to the facility, the facility manager layer concentrates on sequential control and data processing.

At the top level is the HMI layer, which is responsible for interfacing with devices in the system. The PLC software includes a module for handling the interface with the HMI in the module related to the equipment control, so that the module is directly affected by changing the requirements for the HMI. The HMI has a lot of change according to various needs of the factory operator, so it must be separated into independent modules.

Referring back to FIG. 4, the module generation unit must be performed by a program and a task to which each module is assigned, and a subcomponent that is a detailed design of the module, for the modules constituting the PLC software. Provides an environment for editing the handler (hanler), the component and the coordinator responsible for the control of the service and the controller and the controller (controller), and generates a module based on the input contents corresponding to the provision.

The module generator generates a new module by loading and editing a module from the storage 200 using an editor or by editing a PLC code of an existing Standard Template Library (STL) format.

Depending on the type of module, the editor may provide a graphical editing environment in the form of diagrams such as state charts and flow charts, and may also provide a text editing environment. In text editing environment, existing PLC code of standard template library (STL) format can be loaded and used.

6 is a metamodel showing a relationship between modules constituting PLC software.

Referring to FIG. 6, one software may be composed of one or more tasks. One task may have n programs, but generally one program exists in one task. It has a coordinator that manages the entire program. The coordinator is used to manage the operation mode of the factory.

In addition, the program may be composed of n components. Modules belonging to the HMI layer and the facility management layer of the present invention correspond to components.

A component can in turn be composed of several subcomponents and n handlers. Handlers are classified based on the services they need to perform, that is, operations. For example, if a ladle turret consists of one component in a steel mill, the handler is responsible for rotating the ladle turret and lifting the arm. Finally, the handler consists of one coordinator, n controllers, and a processor. The coordinator used by the handler is a more local element, managing the mode of operation of the operation. The number of controllers corresponding to each operation mode is determined. For example, when operating in automatic and manual modes, the handler must include controllers for automatic and manual modes. Regardless of the controller associated with the mode, there is a controller for the output or driver. The number of controllers depends on the number of outputs that must be controlled for operation. The final component of the PLC software, the processor, is responsible for feedback or data processing. For example, if the handler needs an encoder for position control, the processor-related content is handled by the processor.

Figure 7 is an example of the structure of the control software of the ladle turret of the playing process reflecting the meta-model according to the present invention.

Referring back to FIG. 4, the data model generator of the PLC software writer 100 processes data used in each module to generate a data model of a structure in which access of other modules other than the corresponding module is restricted.

Specifically, in the case of PLC software that is heavily influenced by the output data, since the physical address of the input / output data is directly used inside the module, it is affected by the input / output change. This prevents PLC software analysts from focusing on modules.

In order to solve such a problem, as illustrated in FIG. 8, the data model generation unit performs PLC I / O data, which is input / output data, data used by each module, interface data, which is data of another module used by the corresponding module, and performs the module. The result is divided into reference data that collects data used by other modules, and the PLC I / O data and interface data are copied into the module to form a data model with the reference data existing in the module.

The PLC input / output data, interface data, and reference data are stored in the input / output data area, the interface data area, and the reference data area in the storage 200 allocated to the corresponding module, respectively.

By copying the PLC I / O data and interface data to the storage 200 corresponding to the module and localizing it, the developer concentrates on the logic necessary internally using only the address value of the storage 200 without worrying about the physical address change of the external input / output data. To develop software. Subsequently, if there is a change in the reference data of the external module, it is possible to respond to the external change by modifying only the part corresponding to the data interface or input / output of the module. In other words, the data is localized inside the module, allowing reuse of the module.

8 is useful for implementing data hiding. However, since the data of another module is copied, the memory capacity used is twice as conventional. Accordingly, the memory capacity problem may limit the implementation of the PLC.

As a method for overcoming such capacitive limitations while supporting data hiding as it is, the data model generator may provide an environment in which design and implementation are divided according to the method illustrated in FIG. 9.

Referring to FIG. 9, in the design, after mapping reference data performed by one module to an address of an internal storage, an actual reference address is mapped to an address connected to the internal storage using a mapping table before the actual software is PLC down. To change. In other words, the preprocessing process solves the problem of increasing the memory capacity by changing the internal storage address to the actual address value before the actual compilation process.

In this method, you only need to keep separate mapping tables for physical addresses and internal storage addresses during the design phase.

In the present embodiment, the module asset manager 300 stores the module generated by the PLC software writer 100 in the storage 200, or stores the module stored in the storage 200 according to a specific search condition. Perform the function called.

In this embodiment, the data model asset manager 400 registers the data model generated by the PLC software builder 100 in the repository 400, or the module asset manager 300 stores the module stored in the repository 400 in the PLC software. When importing into the builder 100, the data model mapped to the corresponding module is loaded from the repository 400 to the PLC software builder 100.

In this embodiment, the module-operation condition combiner 500 sets or operates conditions set by the user for lazy bindings created by the user when editing the module in the module editor of the PLC software writer 100. Selecting the operating conditions stored in the asset manager 600 serves to create a complete module using the information.

The late binding conditional technique is for example:

COND1 = $ CONDITION $

In the above example, COND1 is a variable that stores true / false that is the result of the condition, but $ CONDITION $ does not know what the condition is. However, this conditional expression may be changed as follows using the operating condition stored in the module-operating condition combiner 500.

COND1 = A and B and C

or

COND1 = A and B and (C or D)

By linking conditions to result variables when creating products, you can reduce the complexity of PLC programs and drive design-driven application software development.

In this embodiment, the operating condition asset manager 600 performs a function of storing the operating condition set by the user.

The above-described examples will be described in terms of (1) module development, (2) PLC software development, and (2) PLC program maintenance.

(1) module development

The module generator of the PLC software writer 100 provides an environment for editing a module from the storage 200 or PLC code of an existing STL format using an editor.

The editor may provide a graphical editing environment in the form of diagrams such as state charts, flow charts, etc., depending on the type of module being edited, or may provide a text editing environment.

The module thus created is then stored in storage 200 for reuse in PLC software development.

(2) PLC software development

The PLC software builder 100 provides an environment for writing PLC software in a top-down hierarchical structure in the following order: HMI layer, facility manager layer, library / network manager layer, and system function layer. In response, when a user selects a module generated in the storage 200 or a module generated by the module generator, macro processing of the selected modules for generation of the PLC software is performed. In other words, by macro-processing the modules selected by the user, only the code for implementing the selected modules is applied to generate the completed PLC software.

(2) PLC software maintenance

If an error occurs in the PLC software, you can correct it in the following way.

First, when the module itself needs to be modified, the module generator of the PLC software builder 100 modifies the module, stores the modified module in the storage 200, and uses the modified module to generate PLC software in the architecture component. Regenerate

Next, if you do not need to modify the module, consider whether you need to modify the data model. When the data model needs modification, the data model generator of the PLC software writer 100 modifies the data model and stores the data model in the storage 200. The PLC software is regenerated by the architecture component using the modified data model. .

Finally, if no modification of the module and data model is required, the architecture component modifies the hierarchical structure of the modules included in the PLC software.

According to the present invention, the PLC software can be modularized from an object-oriented perspective, the modules can be broken down in a top-down manner, and the relationships between the modules can be structured, thereby improving the readability and maintainability of the PLC software. In addition, since interdependencies between modules are removed through the interface method between modules, the compatibility and reusability of software modules are increased. Therefore, it is easy to modify PLC software, which is difficult to modify in the past, and it becomes possible to capitalize PLC software. Maintenance work time is reduced.

In the above-described embodiments of the present invention, the present invention has been described and described with reference to specific embodiments, but the present invention is not limited thereto, and the scope of the following claims is not limited to the scope of the present invention. It will be readily apparent to those skilled in the art that the present invention may be variously modified and modified.

1 is a general execution process flowchart of the PLC software.

2 is a block diagram showing a general data management structure of the PLC software.

3 is a block diagram illustrating a data management structure according to the prior art.

4 is a block diagram illustrating a system for providing a PLC software development environment according to the present invention.

5 is a block diagram illustrating a PLC software architecture in accordance with the present invention.

6 is a block diagram illustrating a PLC software metamodel according to the present invention.

7 is a block diagram illustrating a ladle turret control module constructed based on a PLC software metamodel according to the present invention.

8 is a block diagram for explaining an embodiment of a data management structure according to the present invention.

9 is a block diagram for explaining another embodiment of a data management structure according to the present invention.

Claims (10)

Module generation unit for creating modules used in PLC software, architecture configuration unit for layering modules constituting PLC software, and data of each structure that process data used in each module to restrict access of modules other than the corresponding module PLC software creator including a data model generator for generating a model; And A repository for storing modules and data models generated by the PLC software writer; PLC software development environment providing system comprising a. The method of claim 1, The module generation unit, A PLC software development environment providing system, comprising: providing an environment for inputting a program and a task assigned to the module and a detailed design of each module, and generating a module based on the input contents corresponding to the provision. The method of claim 1, The architecture generating unit provides a PLC software framework including an HMI layer, a facility manager layer, a library layer, a network manager layer, and a system function layer, and layeres modules constituting PLC software based on the PLC software framework. PLC software development environment providing system, characterized in that. The method of claim 3, The HMI layer is PLC software development environment providing system comprising a module that manages the interface between the programmable logic controller (PLC) and the control target equipment. The method of claim 3, The facility manager hierarchy, PLC software development environment providing system comprising a module for controlling the movement of the control target equipment. The method of claim 3, The library layer is, PLC software development environment providing system comprising a module for controlling the operation sequence and data processing of the equipment to be controlled. The method of claim 3, The network manager layer, PLC software development environment providing system comprising a module responsible for communication between a programmable logic controller (PLC) and the control target equipment. The method of claim 1, The data model generation unit, The data used in each module is divided into I / O data, reference data that is the data of the corresponding module used in other modules, and interface data that is the data of other modules used in the corresponding module, and I / O data and interface data are copied to the corresponding module. PLC software development environment providing system, characterized in that the data model is configured with the reference data present in the module. The method of claim 1, The reservoir is The PLC software development environment providing system, characterized in that for storing the data model mapped to the module that is allowed to access the data model. The method of claim 1, A module asset manager configured to store modules generated by the PLC software writer in the storage and to load modules stored in the storage to the PLC software writer; A data model asset manager configured to store a data model generated by the PLC software writer in the storage and to load a data model stored in the storage to the PLC software writer; An operating condition asset manager for storing operating conditions of the facility to be controlled; And A module that generates a complete module by combining the selected operating condition with the module generated by the PLC software writer when the user sets an operating condition or selects an operating condition stored in the asset manager for late combined conditional expressions written by the user. Operating condition combiner; PLC software development environment providing system further comprising a.

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